title: Effectiveness of lifestyle interventions on obstructive sleep apnea (OSA): systematic review and meta-analysis.
abstract: BACKGROUND
  Obstructive sleep apnea (OSA) is a common sleep disorder associated with several adverse health outcomes. Given the close association between OSA and obesity, lifestyle and dietary interventions are commonly recommended to patients, but the evidence for their impact on OSA has not been systematically examined.
  
  
  OBJECTIVE
  To conduct a systematic review and meta-analysis to assess the impact of weight loss through diet and physical activity on measures of OSA: apnea-hypopnea index (AHI) and oxygen desaturation index of 4% (ODI4).
  
  
  METHODS
  A systematic search was performed to identify publications using Medline (1948-2011 week 40), EMBASE (from 1988-2011 week 40), and CINAHL (from 1982-2011 week 40). The inverse variance method was used to weight studies and the random effects model was used to analyze data.
  
  
  RESULTS
  Seven randomized controlled trials (519 participants) showed that weight reduction programs were associated with a decrease in AHI (-6.04 events/h [95% confidence interval -11.18, -0.90]) with substantial heterogeneity between studies (I(2) = 86%). Nine uncontrolled before-after studies (250 participants) showed a significant decrease in AHI (-12.26 events/h [95% confidence interval -18.51, -6.02]). Four uncontrolled before-after studies (97 participants) with ODI4 as outcome also showed a significant decrease in ODI4 (-18.91 episodes/h [95% confidence interval -23.40, -14.43]).
  
  
  CONCLUSIONS
  Published evidence suggests that weight loss through lifestyle and dietary interventions results in improvements in obstructive sleep apnea parameters, but is insufficient to normalize them. The changes in obstructive sleep apnea parameters could, however, be clinically relevant in some patients by reducing obstructive sleep apnea severity. These promising preliminary results need confirmation through larger randomized studies including more intensive weight loss approaches.
authors.affiliation: Birmingham and Black Country NIHR CLAHRC, University of Birmingham, Birmingham, UK ; School of Health and Population Sciences, College of Medical and Dental Sciences, University of Birmingham, UK.
authors.forename: Marzieh Hosseini
authors.initials: MH
authors.lastname: Araghi
authors.forename: Yen-Fu
authors.initials: YF
authors.lastname: Chen
authors.forename: Alison
authors.initials: A
authors.lastname: Jagielski
authors.forename: Sopna
authors.initials: S
authors.lastname: Choudhury
authors.forename: Dev
authors.initials: D
authors.lastname: Banerjee
authors.forename: Shakir
authors.initials: S
authors.lastname: Hussain
authors.forename: G Neil
authors.initials: GN
authors.lastname: Thomas
authors.forename: Shahrad
authors.initials: S
authors.lastname: Taheri
mesh_terms: D004038:Diet, Reducing; D006801:Humans; D009043:Motor Activity; D040242:Risk Reduction Behavior; D020181:Sleep Apnea, Obstructive / Q000628:therapy*; D016896:Treatment Outcome; D015431:Weight Loss
keywords: Lifestyle Intervention; meta-analysis; obesity; obstructive sleep apnea; systematic review